metricsInitialization.java

static {
    // Collect jvm and system metrics by default
    Metrics.registerMetricSet("jvm.gc", new GarbageCollectorMetricSet());
    Metrics.registerMetricSet("jvm.memory", new MemoryUsageGaugeSet());
    Metrics.registerMetricSet("jvm.threads", new ThreadStatesGaugeSet());
    Metrics.registerMetricSet("jvm.runtime", new RuntimeMetricSet());
    Metrics.registerMetricSet("jvm.os", new OperatingSystemMetricSet());
    Metrics.registerMetricSet("jvm.filesystem", new FileSystemMetricSet());
    Metrics.registerAll("jvm.buffers", new BufferPoolMetricSet(ManagementFactory.getPlatformMBeanServer()), Metrics.getMetricRegistry());

    // Register the basic health check
    Metrics.registerHealthCheck("DeadlockDetection", new ThreadDeadlockHealthCheck());

    // Register metrics for the logger (it's the WTF per second metric, very important)
    final LoggerContext factory = (LoggerContext) LoggerFactory.getILoggerFactory();
    final Logger root = factory.getLogger(Logger.ROOT_LOGGER_NAME);
    final InstrumentedAppender metrics = new InstrumentedAppender(registry);
    metrics.setContext(root.getLoggerContext());
    metrics.start();
    root.addAppender(metrics);
}